Morphological Characterization of Buds Being Donors of Apex for Molecular Confirmation of Differentiation of Meristem into Permanent Tissues of Stone Fruit Trees (Prunus sp.)

Molecular confirmation of the process of differentiation of meristematic tissue of plants is primarily based on histomorphological characterization of the tissues carrying these processes. For perennial plants – fruit trees, the knowledge of these processes is important to define runtime type and pomotechnical treatments but also to identify the genes responsible for determination of the apices into a generative phase of differentiation. Which apex extraction techniques will be applied depends on the structure of buds, i.e. whether an apex differentiates only into generative elements – pure flower buds, or the differentiation goes into two directions: differentiation of leaf primordium with axillar meristematic dome and differentiation of generative elements of flowers in the peak or lateral zone of an apex – mixed buds. The fruit trees of the genus Prunus have purely flower buds and for this purpose the whole apex is taken, between protection – cover leaves, on lateral positions of all collateral buds at shoot nodes. The moment of initiation of determination and the dynamics of differentiation of generative buds are different at different type of shoots on a tree. It is therefore necessary to know the shoots growth cessation time which is in correlation with apex determination. Fruit trees of the genus Prunus are ending the growth of shoots by rejection of shoot peaks, and the cast away time depends on the type, length and the position of shoots.